Ethyl cellulose composition containing di-tertiary-octyl diphenyloxide



Patented July 22, 1952 1 was ,E-THYL oeIJLULosEooMPosumN con- TAINING- DIy- TERTIARY OCTYL PHENYLOXIDE- Earle L. Kropscott and Paul 1a. Lipiie, J12, Mia land, Mich as'si'gnor's to The Dow Chemical- Company, Midland, Mich., .a; corporation of 1 1 Delaware mass ng; Application June 4, 1947,

Serial N0. 752,565

6 claims- (01. 10s 1ss The present invention relates a specific compositions of ethyl cellulose, plasticized with di-tertiary-octyl diphenyloxide', having a unique combination of properties which makes the compositions especially valuable for use in extrusion or in compression or injectio operations.

It is common experience that aplasticizer may contribute one or two desirable properties to a thermoplastic material and'at the same time may exert an undesirable influence on other prop erties. Thus, if a plasticizer improves the fleximolding bility, or if it increases thepotential elongation of articles made of a'particular plastic, it is comspecific effect on one or two properties of interest in a particular use for the composition, and differently modified compositions are required whenever emphasis in use is placed upon some other property. While various plastic compositions are sold as general purpose plastics,

theseare usually characterized by a combination of barely acceptable values for many properties and by outstanding values for none of them;

It is an object of this invention to'pro'videan I ethyl cellulose plastic composition suitable for use in extrusion and molding operations at moderate temperatures and pressures, which composition has the following unique combination of properties: rapidly hardens after a shaping operation, to form strong articles capable of greaterelongation, having greater hardnessand impact strength and lower "water absorption than ".the usual. general purpose andlowxtemperature types or ethyl cellulose plastics, and at least as good dielectric ro ert es as the ethyl cellulos compositions specificallyrecommended "for dielectric uses.- A particular objectisfto provide an et hyl'cellulose composition especially adapted for use 'in"electricalinsulation, and having im proved hardness andimpac't'str'ength; and lower water absorption values than ethyl cellulose sion operations.

compositions heretofore known and recommends.

ed for such use. A more general object'is th provision of a plasticized ethyl cellulose composition suitable for use in films, lacquers, and other coatings as well as in molding and extru- Other and related objects may become apparent from'the following description of the invention. r v V v It has now been found that, an ethyl 'cellulose composition may be prepared, having all'of the desiredproperties enumerated above, comprising, as-the essential ingredients, a molding or .lfilm- I forming grade of ethyl, cellulose (usually a'bout 45 to 48.5 per cent ethoxyl, though somewhat more-highly etherified' ethyl cellulose mayjbe used) and di-tertiary-octyl diphenyloxida'the latter being present in amountsQirom-Z, to 30 per cent of the combined weight of ethyl cellulose and plasticizer. For molding and extrusion purposes the ethyl cellulose will usually have an ethoxyl content. of 45 to 47.5Lper cent and the amount of plasticizer will yary'frOm 5f to 20 per cent. v

The di-tertiary-octyl oliphenyloxide maygbe prepared by a condensation of cli-isobutylene with diphenyloxide (phenyl ether) in the presence of a Friedel-Crafts catalyst such as aluminum chloride, and fractional distillation of the resulting product. The compound, or. mixture of isomeric compound .hr'e employed. "as" "a plasticizer, boils "at 2l0' 2'l5' C. at 3 nullim tors of mercury, bsolute "pressure. It ha's'ja density of 0.944 to 0.952 at'ZO? to 25 Cs, refraetivein ex of about 1.525 at 25 C. referredto the D" li eiof sodium, and a jvis'cosity of the general orderflof 5,000 to 7,000 centisitolies at 25 C. .and about 40 centistokesat .CL When carefully" distilled,

it is a colorless lidl iijdfbutlnay 'carryafsught yellow coloration as com'mreiauyfproduce Typical plastic formulations ,"c inprisingf-ethyl cellulos'e'and div-tertiary o'ctyl diphjenyloxide," in proportions particularlyadapted for-three typical fabrication operations, are'z" Formula I represents a composition for general purpose molding and extrusion uses, and is especially desirable for injection molding. Formula II gives extruded articles of high rigidity because the molded articles may be ejected from the die after a shorter cooling period than required with many ethyl cellulose molding com- Ethyl cellulose, 46% ethoxyl, 75 centipoises Plasticizer:

.Di-tertiary-octyl diphenyloxide Liquid polymer of alpha-methyl styrene (molec weight 300-600) Mono-phenyl di-(ortho-xenyl) phosphat '2-ethyl-hexyl ester'of l2-hydroxy stearic ac Methyl ester of l2-hydroxy stearic acid. Refined mineral oil Pigment v "I Tensile strength, pounds per square inch Elongation, percent Rockwell superficial hardness, M( ,-t in; ball, kg.l00 kg.) Impact strength, loot pounds per inch:

At 21 0., notched- At 21 0., unnotched At 18 0., notched At 18 (3., unnotched Water absorption, per cent gain after 24 hours, immersion Dielectric constant:

Thus, it is seen that the composition of Formula I, typifying the present invention, is superior in all respects to the usual type of general purpose molding and extrusion composition, and is at the same time equivalent in. critical'properties to compositions specifically designed for dielectric uses or, for use where low temperaturesare to be encountered. Formula I gives moldings having lower water absorption values than any of the comparative compositions.

The new plastic compositions offer advantages, not only .in the properties of articles fabricated therefrom, as in the foregoing table, but also'in ease of handling during the fabrication. This. is due to the fact that di tertiary-octyl diphenyloxide greatly reduces the softening, and. hence the extrusion or molding, temperature of ethyl cellulose compositions" without unduly softening the finished article. This combination of properties makes it possible, for example, to extrude the new compositions in shapes of irregular crosssection without the need for complex equipment to support and carry the extruded material away from the orifice until thoroughly cold. It also to console having high resistance to thermal distortion 5 positions. It is noted, as an additional advantage (high heat distortion test). Formula III repin fabrication, that thenew compositions require resents a composition useful in compression moldno mold-release agents, anclthat they form highly ing and other low pressure forming operations. glossy molded articles, both of which traits are To illustrate the advantages of the new com-= rare in ethyl cellulose molded articles. positions, moldings of the one designated above 10' The plasticizer here concerned is soluble in as Formula I will be comparedas to many signifi 1 all common lacquer solvents used with ethyl celcant properties with moldings of older commer lulose, and itfmay be used toplasticize ethyl cial ethyl cellulose compositions specifically cellulose'films'and lacquer coatings. Such films designated for particular uses. 'One of the comretain surprisingly high strength values, comparative formulations is known as an electrical l5 pared with the unmodified films, but have much grade, because of its dielectric properties and low" lower softening and melting points than the water absorption values. Another is unusual beunplasticized film. It is this same combination cause molded and extruded articles therefrom of low softening point and high retention of have good flexibility and high impact strength at I hardness and strength which makes the new low temperatures. The third is a commercial '2'0"compositions so useful in making molded and general purpose molding and extrusion comextruded articles, as described above. The folposition.- The comparison of properties of these lowing table illustrates the effect of di-tertiaryvarious molded compositions appears in the foloctyl diphenyloxide on the strength and the lowing table. softening point of ethyl cellulose film.

For- Elec- LOW General mulaI trical T331132? Purpose s3 s1 s1 0. 07 0.66 j 1. as 1.30 2.43 3.90

Wherever reference is made herein to the viscosity rating of ethyl cellulose, in CEUMDOISES, the determination has been made on a 5 percent solution thereof, by weight, in a 70:30 mixture of toluene and ethanol, by volume. i T V This invention is limited to di-tertiaryoctyl diphenyloxide as the principal modifier in ethyl cellulose compositions because mono-tertiaryoctyldiphenyloxide is .too volatile and does not provide compositions having thegeneral utility provided by the di-octyl compound.

'Ihe invention is limited to' ethyl cellulose compositions, because di-tertiary-octyl diphenyloxide, while giving the appearance of compatibility in solutions of some other plastics, is incompatible, or nearly so, in films and molded articles made of such typical plastics as cellulose acetate, cellulose nitrate, cellulose acetate butyrate, cellulose acetate propionate, polyvinyl butyral, vinyl chloride-vinyl acetate copolymer, polyethylene, polyvinyl chloride, and vinylidene chloride copolymers with vinyl chloride or with acrylonitrile.

We claim:

1. A composition of matter consisting essentially of ethyl cellulose and a plasticizing concentration of di-tertiary-octyl diphenyloxide boiling at 210 to 215 C. at 3 millimeters of mercury, absolute pressure.

2. A composition of matter consisting essentially of ethyl cellulose of at least about 45 per cent ethoxyl content and from about 2 to about 30 per cent of its combined weight therewith of di-tertiary-octyl diphenyloxide boiling at 210 to 215 C. at 3 millimeters of mercury, absolute pressure. 7

3. A plastic composition consisting essentially of ethyl cellulose having an ethoxyl content of from about 45 to about 47.5 per cent, and from about 5 to about 20 per cent of its combined weight therewith of di-tertiary-octyl diphenyloxide boiling at 210 to 215 C. at 3 millimeters of mercury, absolute pressure.

4. A plastic composition consisting essentially of about 83 parts by weight of a molding grade 6 of ethyl cellulose and about 16 parts by weight of di-tertiary-octyl diphenyloxide boiling at 210 to 215 C. at 3 millimeters of mercury, absolute pressure.

5. A plastic composition consisting essentially of about 94 parts by weight of a grade of ethyl cellulose suitable for extrusion and about 5 parts by weight of di-tertiary-octyl diphenyloxide boiling at 210 to 215 C. at 3 millimeters of REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,109,514 Van Duzee et al. Mar. 1, 1938 2,121,723 Bass et al June 21, 1938 Coleman et al. Aug. 19, 1939 9 OTHER REFERENCES Ethyl Cellulose, Hercules Powder Co. (1944),

' page 15. 

1. A COMPOSITION OF MATTER CONSISTING ESSENTIALLY OF ETHYL CELLULOSE AND A PLATICIZING CONCENTRATION OF DI-TERTIARY-OCTYL DIPHENYLOXIDE BOILING AT 210* TO 215* C. AT 3 MILLIMETERS OF MERCURY, ABSOLUTE PRESSURE. 